This invention relates generally to electronic gaming machines interconnected by a computer network and more particularly to a method and apparatus for dynamically adjusting bonusing thresholds to accommodate players on linked gaming machines during off-peak as well as peak playing periods.
Casinos typically include electronic gaming machines (EGMs) such as slot machines and video poker machines. These games are referred to herein as the xe2x80x9cprimary gamexe2x80x9d associated with the particular gaming machine. Slot machines, for example, usually include three reels that each have a plurality of symbols printed thereon. After the player applies a wager to the machine, he or she starts play by triggering a switch that starts the reels spinning. Each reel stops at a random position and thereby presents three symbolsxe2x80x94one from each reel. Some combinations of symbols do not pay any jackpot. Others pay varying amounts according to predetermined combinations that appear in a pay table displayed on the machine and stored in the gaming machine""s programmable read-on memory (PROM).
More recently, multiple gaming machines have been linked together into groups of machines that share the same bonus pool. The advantage of the progressive system is that the bonus pools from individual machines can be pooled to form larger awards, which in turn attract more players. When taken to the extreme, progressive bonuses can be pooled together not only from machines in different areas of the casino, but also from different casinos in different states. Recently developed bonusing systems are implemented using bonus servers distributed over a network, such as disclosed in co-pending application Ser. No. 08/843,411, filed Apr. 15, 1997 and assigned to the Assignee of the present application (the ""411 application), which is incorporated herein by reference for all purposes. Also incorporated herein by reference for all purposes is U.S. Pat. No. 5,655,961, assigned to the Assignee of the present application (the ""961 patent), which also discloses bonuses that can be implemented by bonus servers over a network.
In a typical bonusing system, bonus prizes are awarded on top of regular jackpot pay table prizes when a progressive bonus pool meets or exceeds a predetermined, first threshold value. Exceeding this threshold value starts a bonus period. A predefined percentage of coins wagered on the games are placed into a common bonus pool. The amount of the bonus pool is then continually compared to the first threshold value. This first threshold value is either fixed or is selected at random at the start of each pool accrual cycle. When the pool reaches the threshold value, the bonus period commences in which bonus prizes are awarded to all eligible games on the link, or alternately are awarded to some subset of eligible machines on the link, which meet some other criteria. Typically, eligibility implies that the machine has a person who is playing at some predefined minimum acceptable play ratexe2x80x94for instance three coins every thirty seconds. The awarded bonus prizes are then decremented from the bonus pool. When the bonus pool falls below a second (lower) threshold, the bonus period is stopped until the bonus pool again rises beyond the predetermined, first threshold value.
With this method of funding and awarding bonuses, the frequency of occurrence for the bonus award depends upon how many machines are being played, how fast the players are playing, and how many coins are being wagered on each game played. The greater the rate of play, the faster the pool rises. The faster rising pool means more frequent threshold crossings, and thus more frequently occurring bonus periods and award payments. Under most conditions, this is a good effect. As more people play, the pool rises faster and the bonus awards are paid more frequently.
A major drawback with previous progressive bonusing schemes such as the one described above is that a person playing at non-peak times may never get to see a bonus event. If there is only one person playing on a bonus link that includes one-hundred games, the linked bonus will occur one-hundred times less frequently than if all of the games are being played. Consequently, the lone individual has a much different play experience than the person playing at peak times who gets to see the linked bonus awards occurring frequently.
Accordingly, a need remains for an improved gaming system that dynamically adjusts its bonusing scheme to accommodate the appropriate number of players during off-peak and well as peak playing times.
It is, therefore, an object of the invention to adjust the threshold to initiate a bonus period depending upon the number of eligible gaming machines on a bank of machines coupled together over a network link.
The invention comprises a method and apparatus for awarding bonuses over a gaming network having a plurality of gaming machines interconnected by a network. Play is allowed to occur on a plurality of gaming machines as the bonus pool, common to the gaming machines over the network, is incremented responsive to play on the plurality of gaming machines. The total number of eligible gaming machines is detected responsive to play on each of the plurality of gaming machines. A first threshold value is set in consideration of the total number of eligible gaming machines detected. A bonus period would be initiated when the bonus pool satisfies the first threshold value. Accordingly, the threshold necessary to start the bonus period would be low if few players are detected, and high if many players are detected. Bonus amounts are paid from the bonus pool to the eligible gaming machines after which time the bonus period would end. Alternatively, bonuses would be paid responsive to detected triggering events, such as the occurrence of a special symbol on the slot machine reels during the bonus period. The bonus period would end when the bonus pool moves below a second threshold value after which time the bonus pool would be incremented for subsequently occurring bonus periods.
One advantage of the bonusing system above is that awards can be varied from machine to machine during the linked bonus period. Additionally, the bonusing system has a demonstrable effect on game payback percentage, regardless of the rate of play across the bank of games, to encourage play and increase enjoyment.
The foregoing and other objects, features and advantages of the invention will become more readily apparent from the following detailed description of a preferred embodiment of the invention that proceeds with reference to the accompanying drawings.